feat: allow choosing user on remote commands

cli/app/cmd.go

@@ -32,6 +32,14 @@ var localCmdFlag = &cli.BoolFlag{
 	Destination: &localCmd,
 }
 
+var remoteUser string
+var remoteUserFlag = &cli.StringFlag{
+	Name:        "user, u",
+	Value:       "",
+	Usage:       "User to run command within a service context",
+	Destination: &remoteUser,
+}
+
 var appCmdCommand = cli.Command{
 	Name:    "command",
 	Aliases: []string{"cmd"},
@@ -52,6 +60,7 @@ Example:
 	Flags: []cli.Flag{
 		internal.DebugFlag,
 		localCmdFlag,
+		remoteUserFlag,
 	},
 	BashComplete: autocomplete.AppNameComplete,
 	Before:       internal.SubCommandBefore,
@@ -200,6 +209,11 @@ func runCmdRemote(app config.App, abraSh, serviceName, cmdName, cmdArgs string)
 		Tty:          true,
 	}
 
+	if remoteUser != "" {
+		logrus.Debugf("running command with user %s", remoteUser)
+		execCreateOpts.User = remoteUser
+	}
+
 	// FIXME: avoid instantiating a new CLI
 	dcli, err := command.NewDockerCli()
 	if err != nil {